Underlap forming instrumentalities for wrapping machines



April 21, 1959' c. B. cRoss 2,882,665 UNDERLAP FORMING INSTRUMENTALITIES FOR WRAPPING'MACHINES Filed March 22, 1957 4 Sheets-Sheet 1 ATTORNEYS C. B. CROSS April 21, 1959 UNDERLAP FORMING INSTRUMENTALITIES FOR WRAPPING MACHINES Filed March 22. 1957 4 Sheets-Sheet 2 u III 4.1Illllllll Ill!uulllvllllllllllllllwJ 1 L? I m ATTORNEYS CEDRIC B. CROSS N @Ywvmk wl April 1, 1959 c. B. cRoss 2,882,665

UNDERLAP FORMING INSTRUMENTALITIES FOR WRAPPING MACHINES Filed March 22, 1957 4 Sheets-Sheet 3 F I G. 6

INVENTOR. CEDRIC B. CRQSS Y WR VS.

ATTDHNEYS Apnl 21, 1959 c. a. cRoss 2,382,665

UNDERLAP FORMING INSTRUMENTALITIES FOR WRAPPING MACHINES Filed March 22, 1957 4 Sheets-Sheet 4 F I 6. I3

F I 6. I4

WM '52 a 32 52A 3 um llll INVENZ'OR. CEDRIC B. CRO$S QWMWW ATTQRNEYS United States Patent UNDERLAP FORMING INSTRUMENTALITIES FOR WRAPPING MACHINES Cedric B. Cross, Monson, Mass., assignor to Package Machinery Company, East Lougmeadow, Mass., a corporation of Massachusetts Application March 22, 1957, Serial No. 647,769 8 Claims. (Cl. 53-233) The present invention relates to wrapping machines and more particularly to improved means for completing the encirclement of an article in a wrapper.

Wrapping machines of the type disclosed in US. Patent No. 2,810,246, October 22, 1957, have proven to be very effective in increasing the rate at which articles can be wrapped. This in part is due to the novel manner in. which the articles are encircled by a wrapper. One form of the encircling means described therein, which has found particular commercial acceptance, contemplates that partially-encircled articles be gripped at their sides by conveyor means with their bottom portions unsupported and free for rotating underlap forming instrumentalities to complete the encircling operation. While these means are highly effective in wrapping a great variety of articles there are certain types of articles which are difficult to firmly grip on their side edges so that the degree of reliability of the wrapping operation is somewhat reduced. Also, such rotating underlap forming instrumentalities are inherently capable of high rates of operation, possibly higher than any other device for such purposes, it is at times necessary to reduce their speed under certain wrapping conditions, as where relatively wide articles are being wrapped in order to obtain a satisfactory degree of reliability.

Accordingly it is the object of this invention to improve underlap forming instrumentalities of this general type to provide support for the surface on which the underlap is to be formed as well as to improve the reliability of operation of such instrumentalities regardless of the size of the articles, all without reducing the rate at which the underlap forming operation may be carried out.

The above and other related objects of the invention as well as its various novel features will be readily apparent from a reading of the following description of the disclosure found in the drawings and the particular novelty thereof pointed out in the appended claims.

In the drawings:

Fig. 1 is a view showing particularly the improved underlap instrumentalities as incorporated in the wrapping machine disclosed in the above-mentioned patent, certain portions being broken away and taken generally on line I-I in Fig. 2;

Fig. 2 is a plan view of the underlap instrumentalities seen in Fig. 1;

Fig. 3 is a section taken generally on the line HIIIIv in Fig. 2; v

Fig. 4 is a section taken on theline IV-IV in Fig. 2;

,Fig. 5 is a' section taken on the line V-V in Fig. 4;

Figs. 6 through 14 are detailed views of the underlap forming instrumentalities seen in Figs. 1 and 2 sequentially showing their manner of operation; and

Fig. 15 is a section taken generally along the line XV-XV in Fig. 1, showing certain drive elements and with one shaft displaced vertically so as to clarify the lateral positions of such elements. v

I While the underlapforming instrumentalities of this invention have a wide range of utility in packaging machinery a. better understanding is obtained by the present disclosure of the manner in which they can be incorporated in a wrapping machine of the type disclosed in the above-mentioned patent. The conveyor means 20 found in Fig. 1 corresponds to the same conveyor means as are pictured in Fig. 21 of said patent. These conveyor means comprise arms 22, 24 which have resilient pads 26 for gripping articles as they are continuously advanced through the wrapping machine. The conveyor means 20 are driven by sprockets 28 at a fixed rate and in predetermined timed relation to the various instrumentalities of the wrapping machine. Each article is partly encircled in a wrapper and gripped by the arms 22, 24 all in a manner fully shown in the above designated patent.

Each article is therefore advanced toward the improved underlap forming instrumentalities of this invention along a plate or platform 30 with a wrapper partially encircled thereabout. It will be noted (Fig. 1) that one end of the wrapper lies against the bottom face of the article as it is advanced along the the other end of the wrapper trails behind.

Said underlap forming instrumentalities comprise transverse bars 32 which are connected at each end to spaced roller chains 34 and 36. These roller chains are respectively trained over sprockets 38, 40, 42 and sprockets 44, 46, and 48 (Figs. 1, 2 and 15). The sprockets 38 and 44 are secured to a shaft 50 which is journaled'in bearings 52, 54 carried on the machine side Walls 56,

58. The sprockets 40, 46 rotate about antifriction bear-- ings on a fixed transverse shaft 59 while sprockets 42, 48 are carried in a similar manner on a fixed transverse shaft 61. The bars 32 are guided for movement in a path parallel to and contiguous with the path of movement of the bottom faces of the articles. Such con tiguous movement is maintained substantially throughout the length of an opening between the plate 30 and a second spaced plate or platform 60 by chain guides 62 and 64 (Figs. 1, 2 and 15) which control the upper runs of chains 34, 36. The guides 62, 64 are set apart by spacers 66 and mounted on uprights 68 extending from a transversely disposed channel member 69 secured at its respective ends to the side frames 56, 58 by way of pads 71, 73.

The movement of the conveyor 20 (Fig. 1) and the movement of the traveling bars 32 are tied together by a chain passing around sprockets 77, 79 on shafts 50, 59 and a sprocket (not shown) secured to shaft 81 to which the conveyor sprockets 28 are also secured. All

chains and sprockets are then driven by a chain 83 extending from a power source, not shown, and passingrated by single bars. In Figs. 6 and 7 the bars of the articulated groups are identified 32a, 32b, 32c, 32d, 322

and 32], While the single bar is denoted as 32g. As will be apparent from the following description of the operation the single bars 32g and the leading bars 32a of each group are the main bars for manipulating the wrapper ends as an underlap is formed, while the remaining bars in each group provide varying degrees of support for the article. In fact certain size articles are adequately supported by less than the full group of bars. Thus bar 32b may be omitted as seen in Figs. 8-14.

With this arrangement as an article A (Fig. 6) is carried towards the end of plate 30 it will be seen that plate 30 while one end x of the wrapper W is between the plate 30 and thebottom face of the article A. The other end y of the wrapper W is trailing behind the article as is better seen in Fig. 7. When the article A is carried beyond the end of plate 30 it will be supported by the bar 32d (Fig. 7.). As the article A continues to advance (Figs. 8, 9 and '10) it is progressively supported by the'bars 32c and 32f. After the trailing edge of the article A passes beyond the end of plate 30 wrapper end y will be supported by the bar 32g which trails and is spaced from the bar 32f. This leaves the wrapper end x free to extend into the opening provided by the spaced plates 30 and 60 either under the influence of gravity or with the assistance of some external force. In the drawing a suction unit 70, later described, may provide :such external force, however, for the present purposes it may be assumed that the wrapper end x falls freely by gravity to the position shown in Fig. 14 as the article A continues to advance progressivelyffrom theposition seen in Fig. 12 to that seen .in Fig. 14. "The bars 32g and 32 support the article (Fig. 13) and then freely permit both wrapper ends to extend (Fig. 14) into the opening between the spaced plates 30 and 60 with the bar 32g interposed between the wrapper .ends. Referring back to Fig. 6 article B having a similar wrapper W with ends x and y shows the next position which article A would assume. Article B is similarly supported by bars 32g and 32 as the wrapper ends at and .y extend further into the opening between the plates 30 and 60. As article B approaches plate 60 (Fig. 7,) bar 32a is approaching the wrapper end as spaced bar 32g is in a position preparatory to folding the wrapper end 2: against the edge of plate 60 to .hold said end awayfrom the bottom face of article B. When the bars 32a and 32g reach the position illustrated in Fig. 8 wrapper end x is folded over against the edge of plate 60, and wrapper end y is being wiped against the bottom of package B. Wiping of wrapper end y against the bottom face of article B is substantially completed in Figs. 9 and 10, continued movement of article 3 and bar 32g releases wrapper end x as the articleis advanced along plate 60 with end x overlying end y. The underlapforming operation is substantially completed in this manner as seen from Figs. 11 and 12. It should be noted that throughout the underlap-forming operation the article (A or B) has been supported by one or another of the bars 32.

As mentioned abovc it may be found desirable to provide some external force to facilitate or assure the extension of one or both of the wrapper ends x and y into the opening between the spaced plates 30 and '60. For such purpose fluid pressure means either as a suction unit orpressure jets have been found preferable.

Thus .the'undersurface of plate 30 (Figs. 2, -4 and .5) is provided with longitudinally extending passageways 90 which open on a plenum 92 formed in transverse plate 94. The plate 94 is carried by a transverse supporting bar 96 having a plenum 98 which is connected to the plenum 92 by holes 100 in the plate 94. Openings 102 in the plate 94 are provided to receive connections from a suitable source of pressurized air and pressurize the plenums 98 and 92. Thus jets of air are directed from the passageways or ports 90 into the opening between the plates 30 and 60 to assist the extension of the wrapper ends x and y into that opening.

Also communicating with the plenum 98 are elbow fittings 104 threaded into the plate 94. Attached tothe other'ends-of the elbows 104 are longitudinally extending pipes 106 spaced outside the path of article travel. Ports 108(Figs. l and 2) direct jets ofair inwardly and downwardly against the upper surfaces of the wrapper ends to further assure their extension into the opening between the plates 30 and 60 so that they may be manipulated by the bars 32 to form an underlay as previously ide scribed. 7

'4 7 While the air pressure means above described have their particular uses, it has been found that the suction unit 70 has particular utility in assuring the extension of the leading wrapper end x into the opening between the plates 30 and 60 especially where wide (in a transverse sense) articles are being wrapped. The suction unit 70 (Figs. 2 and 3) is pivotally connected at one end to a member 110 which'is free to oscillate on :the shaft 61. The other end of the "unit 70 is pivotally connected to a crankarm 112 which is secured by clamp screw 114 to a shaft 116. The shaft 116 is journalcd in bearings 118, 120 and 122 secured respectively to an'upright 124, the upright 68 and the pad 73 (Fig. 2). The crankshaft 116 is rotated-in timed relation to the movement 01"; the bars 32 by a chain 126'which passes around a sprocket 128 secured to said shaft. The chain 126 is driven (Figs. 1, 2 and 15) by a sprocket 130 secured to the shaft 55) and passes around idler sprockets 132, 134 on the shafts59, 61 respectively and an adjustable'takeup sprocket 136. .The suction unit 70 is provided with upwardly directed suctionvports 138 (Fig.2) which are interiorly connected with a flexible tube 140. The tube 140-extends through an opening 142 in the near upright 168 and thento a suction pump or other suitable vacuum source.

The described-mounting of the suction unit'70 results in its being disposed beneath the upper bars 32 through a greater portion of their cycle of operation (Figs. 6-9). Then when the bars 32) and 32g are spaced apart above the unit 70it is raised (by rotation of the crank arm "112) into suchspacing (Figs. .10 and ll). i It will be noted that the bars 323, 32g are beveled-to facilitate this movement. lnFig. 12 it will be seen that the suction ports have engaged the wrapper end x and then in Fig. 13 the positive action of the suction unit in bringing the end x into the opening between the plates 30 and 60 in advance of the bar 32g will be=observed. Engagement of the unit 70 with the wrapper end x is prolonged and thus made more effective by the mounting means employed. In this tegard it should be noted that the unit 70 has a component of movement in the same direction as that of the articles, thus giving more positive assurance that end x will be in advance of bar 32g before it .is released as seen in Fig. 14.

The above described underlap-forming instrumentalities moving in the same direction as the articles at all times provide support for said articles and in addition to the high degree of reliability which they provide, with or withoutfluid pressure assistance, they are capable of extremely fast rates of operation.

Having thus described my invention what I claim as novel and desire to secure by Letters Patent of the United States is:

1. In a wrapping machine, means for continuously advancing articles which are each partially encircled .ina wrapper, with one end of the wrapper laying against the bottom face of the article and the other endtrailing 'therebehind, afirst platform .for-supportingthe bottom-face of such apartially encircled article as it is advanced, a. second platform spaced fromsaid first platform in the direction of article travel to provide an opening into which the wrapper ends extend as the article is progressively advanced by said advancing-means, said first platform having fluid pressure ports directed toward said opening immediately below and-in the direction of article travel for facilitating the extension of said wrapper ends into said opening, longitudinally extendingfluidpressurepipes adjacent and above said opening .and outside the path of article movement saidtpipes havingports angledinwardly 'and downwardly to direct .fluid pressure against said wrapper ends to further facilitate the extension of said ends into said opening, afirst'shaftbeneath said first .platform, a second shaft beneath saidsecond platform, a pairof transversely spaced sprockets on each of'said shafts, a pair ofchains carried by said sprockets, -tranverse bars attached to and extending -.to and extending between said chains,- said bars being arranged in spaced relation along said chains, said arrangement comprising groups of articulated bars each group being spaced from and separated by a single bar, guide rails for the upper runs of said chains, said guide rails being arranged to guide the chains so that the transverse bars will move through a path contiguous with the path of the bottom face of the article as it is being advanced substantially throughout the length of the opening between said platforms, a suction unit having upwardly facing suction ports and pivotally connected at one end to an oscillating member on said first shaft, a crank arm connected to the other end of said suction unit, means for rotating one pair of sprockets in a direction to cause the transverse members carried by the upper chain runs to move in the same direction as the article and at a faster rate and in such predetermined relation thereto that the trailing portion of a group of articulated bars first supports the article as it is first advanced over said 'opening, means for rotating said crank arm in such predetermined relation to the movement of said bars that the ports of the suction unit engage the said one wrapper end to draw it into said opening between said trailing portion and the following trailing single bar, the timed relation of the bar movement to the article advance being such that upon further movement said following single bar holds said one wrapper end against said second platform as the leading portion of the following trailing group of articulated bars engages the other wrapper end and lays it against the bottom face of the article.

2. In a wrapping machine, means for continuously advancing articles which are each partially encircled in a wrapper with one end of the wrapper laying against the bottom face of the article and the other end trailing therebehind, a first platform for supporting the bottom face of such a partially encircled article as it is advanced, a second platform spaced from said first platform in the direction of article travel to provide an opening into which the wrapper ends extend as the article is progressively ad-' vanced by said advancing means, a first shaft beneath said first platform, a second shaft beneath said secondplatform, a pair of transversely spaced sprockets on each of said shafts, a pair of transversely spaced chains carried by said sprockets, transverse bars attached to and extend-' ing between said chains, said bars being arranged in spaced relation along said chains, said arrangement comprising groups of articulated bars spaced from and separated by a single bar, guide rails for the upper runs of said chains, said guide rails being arranged to guide the chains so that the transverse bars will move through a path contiguous with the path of the bottom face of the article as it is being advanced substantially through the length of the opening between said platforms, a suction unit having upwardly facing suction ports and pivotally connected at one end to an oscillating member on said first shaft, a

crank arm connected to the other end of said suction unit, I

means for rotating one pair of sprockets in a direction to cause the transverse members carried by the upper chain runs to move in the same direction as the article and at a faster rate and in such predetermined relation that the trailing portion of a group of articulatd bars first supports the article as it is first advanced over said opening, means for rotating said crank arm in such predetermined relation to the movement of said bars that the ports of the suction unit engage the said one wrapper end to draw it into said opening between said trailing portion and the following trailing single bar, the timed relation of the bar movement to the article advance being such that upon further movement said following single bar holds said one wrapper end against said second platform as the leading portion of a trailing group of articulated bars engages the other wrapper end and lays it against the bottom face of the article.

3. In a wrapping machine, means for continuously advancing articles which are each partially encircled in a wrapper with one end of the wrapper laying against the bottom face of the article and the other-end trailing there behind, a first platform for supporting the bottom face of such a partially encircled article as it is advanced, .a second platform spaced from said first platform in the direction of article travel to provide an opening into which the wrapper ends extend as the article is progressively advanced by said advancing means, a first shaft and a second shaft, a pair of transversely spaced sprockets on each of said shafts, a pair of transversely spaced chains carried by said sprockets, transverse bars attached to and extending between said chains, said bars being arranged in spaced relation along said chains, means for guiding the upper runs of the chains so that the transverse bars will move through a path contiguous with the path of the bottom face of the article as it is being advanced substantially throughout the length of the opening between said platforms, a suction unit having upwardly facing suction ports, means for rotating said sprockets in a direction to cause the transverse members.

carried by the upper chain runs to move in the same direction as the article and at a faster rate and in such pre-, determined relation that the trailing portion of a group of articulated bars first supports the article as it is first advanced over said opening, means for moving said suction unit into and out of the path of movement of the transverse bars on the upper chain runs in such predeter-- mined relation to the movement of said bars that the ports of the suction unit engage the said one wrapper end to draw it into said opening between said trailing portion and the following trailing single bar, the timed relation of the bar movement to the article advance being such that uponfurther movement the single bar holds said one, wrapper end againstsaid second platform as the leading;

portion of a trailing group of articulated bars engages the other wrapper end and lays it against the bottom face of the. article.

4. In a wrapping machine, means for continuously adrection of article travel to provide an opening into whichthe wrapper ends extend as the article is progressively advanced by said advancing means, spaced transverse mem-' bers movable through a path intersecting the path of movement of the wrapper ends extending into said opening, the path of movement of said members being contiguous with the path of movement of the article bottom and means for so moving said members in the same direction as and at a faster rate than the article and in such predetermined timed relation to the movement of the article that one member supports the article as it is first advanced over said opening, a second following spaced member next supports the article and then holds said one wrapper end away from the article bottom and a third following spaced member next supports the article and lays said other wrapper end against the bottom face of the article, continuous advancement of the article bringing said bottom face over said second platform with said one wrapper end overlying said other wrapper end, the article supporting relationships of the spaced members overlapping so that the article is at all times supported as it is advanced over said opening.

5. In a wrapping machine, means for continuously advancing articles which are each partially encircled in a wrapper with one end of the wrapper laying against one face of the article and the other end trailing therebehind, a first plate having a surface along which said one face of such a partially encircled article is advanced, a second plate spaced from said first plate in the direction of article movement to provide an opening into which the wrapper ends extend as the article is progressively advanced by said advancing means, a plurality of transverse members 27 spaced -apart in the direction of article ns-overheat and movable "through a closed path aiportion :er which inter- 'sects'the"path of movement of the wrapper ends extending, the means for moving said spaced members "being adapted 'to m'ove'said members through said intersecting portionin-the same direction'asand at a faster rate than the article and in s'uch'p'redetermined timed relation to'the movement of the article that one of said 'membersholds said one wrapper end clear of said one article 'face as a following member law said other wrapper end against said one article face, "continued advancement of the artielebringing 'said'oneface along saidsecondplatewith said one wrapper end overlying said other wrapper end.

6. 'Ina wrapping machine, means for'continuously a'dvancingarticles which are each partially encircled in a wrapper with one end of the wrapper laying against one face of the article and'the other end trailing-therebehind, a first plate having a surface along which said one face of such 'a partially encircled article'is advanced, a second plate spaced from said first plate in the direction of article movement to provide an opening into which the wrapper ends extend as the article -is progressively ad-. vanced by'said advancingmeans, fluid pressure means for facilitating the extension of both'of said wrapper ends into said opening, a plurality df transverse members spaced apart in' th'e direction of ar'ticle advance and mov able through a closed'path a p'ort ion of 'which inters'e'c'ts the path 'of movement of the wrapper ends extending into said opening, the intersecting portion of the path of movement of said members being contiguous with the path of movement of said one article face, andmeans for "so moving "said members through 'said intersecting portion i'n the same direction as and at a faster rate than the article and in such predetermined timedrelation to the movement of the article that one of said members holds said one wrapper end clear of said one article face as a following member lays said other wrapper end against said one article face, continued advancement of the article bringing said one face alongsaid second plate with said one wrapper end overlying said other wrapper end.

7. In a wrapping machine, means for continuously rectilinearly advancing articleswhich are each partially encircled ina Wrapper with one end-of the wrapper laying against the bottom of the article and the other end trailing therebehind, a first plate along the upper surface of which the article bottom is advanced, a second plate spacedapart' fmm said first plate in :the direction of article movement to provide an opening into which the wrapper ends extend as the article is progressively advanced by said advancing means, the upper surface of said second plate lying in the same plane as the upper surface of'said first plate, a plurality'of transverse members spaced apart in the direction of article advance and movable througha closed path a portion of which intersects the path of movement of the Wrapper ends extending intosaid opening, the intersecting portion of the path of movement of said members being contiguous with the path of movement of the article bottom, and means for so-moving said members through said intersecting portion in the same direction as and at a faster rate than the article and in such predetermined timed relation to the movement of the article that one of said members holds said one Wrapper end clear of said article bottom asa following member lays said other wrapper and against said one article face, continued movement of the article bringing said bottom over said second plate with said one wrapper end overlying said other wrapper end.

8. In a wrapping machine, means for continuously advancing articles which are each partially encircled in a wrapper with one end of the wrapper laying against one face of the article and the other end trailing therebehind, a first plate having a surface along which said one face of such a partially encircled article is advanced, a second plate spaced from said first plate in the direction of article advance to provide an opening into which the wrapper ends extend as the article is progressively advanced by said advancing means, a plurality of transverse members spaced apart in the direction of article advance and movable through a closed path a portion of which intersects the path of movement of the Wrapper ends extending into said opening, the path of movement of said members through said intersecting portion being contiguous with the path of movement of said one article face substantially throughout the lengthof said opening, and means for so moving said members through said intersecting portion in the same direction-as and at 'a faster rate than the article and in such predetermined timed relation to the movement of the article that one of said members holds said one wrapper end clear of said one article face as a following member lays said other wrapper end against said one article face, continued movement of the article bringing said one face along said second plate with said one wrapper end overlying said other wrapper end.

References Cited in the file of this patent FOREIGN PATENTS 757,250 Great Britain Sept. 19, 1956 

